The present invention relates, in general, to materials handling and, in particular, to materials feeding apparatus which delivers controlled amounts of free flowing solid materials to utilization equipment.
There are a number of different types of equipment for feeding free flowing solid materials such as granulated materials, powders, pellets and the like. In one form, known as a "disc" feeder and used commonly for handling granulated material, the material is carried on a horizontally disposed rotating disc. The material passes under a shearing baffle which is set at a height to control the amount of material which is delivered to a material discharge point. At the material discharge point, the material is conducted through chutes and conduits to the utilization equipment.
The disc feeder can be arranged with a disc having a flat top surface on which the material is carried and suitable means for conducting the material from the top of the disc to the utilization equipment after the material has passed under the shearing baffle and reached the material discharge point. Alternatively, the disc can have through holes in which the material is carried and which are closed off at their bottoms by a base over which the disc rotates. The material discharge point is an opening in the base through which the material carried in the through holes is free to fall when the respective through holes clear the base and reach this opening.
A common application of disc feeders is for feeding coloring additives, in the form of granulated material, to an injection molding machine to which the base component of the part to be molded also is supplied. Besides the requirement that such feeders deliver accurately metered quantities of materials regardless of the form of the feeder or its application, such feeders also should be arranged for easy changeover when the material to be delivered to the utilization equipment is to be changed. In addition, such feeders should be relatively easy to disassemble and reassemble when it is necessary to clean or repair the feeder.
Disc feeders which are currently available, while capable of delivering accurately metered quantities of the material being handled, are not arranged for easy changeover of materials to be handled. Typically, the storage hopper, still containing material, along with the disc and associated components is lifted off the base of the apparatus as a unit and the material in the loader hopper is dumped into a storage container. This can be awkward and difficult because of the bulkiness of the equipment and the weight of the equipment and the material in the storage hopper.